Examinando por Autor "Ramos, Miguel"

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Acceso Abierto
Frozen ground and snow cover monitoring in Livingston and Deception islands, Antarctica: preliminary results of the 2015-2019 PERMASNOW project
(Universidad de la Rioja, 2020-02-15) De Pablo, M. A.; Jiménez, J. J.; Ramos, Miguel; Prieto, M.; Molina, A.; Vieira, G.; Hidalgo, M. A.; Fernández, S.; Fernández Menéndez, Susana del Carmen; Calleja, J. F.; Peón, J. J.; Corbea Pérez, A.; Maior, C. N.; Morales, M.; Mora, C.; Ministerio de Economía y Competitividad (MINECO); Universidad de Alcalá; 0000-0002-5038-2022; 0000-0002-0843-3658; 0000-0001-7551-2236; 0000-0002-4496-2741; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Since 2006, our research team has been establishing in the islands of Livingston and Deception, (South Shetland archipelago, Antarctica) several monitoring stations of the active layer thickness within the international network Circumpolar Active Layer Monitoring (CALM), and the ground thermal regime for the Ground Terrestrial Network-Permafrost (GTN-P). Both networks were developed within the International Permafrost Association (IPA). In the GTN-P stations, in addition to the temperature of the air, soil, and terrain at different depths, the snow thickness is also monitored by snow poles. Since 2006, a delay in the disappearance of the snow layer has been observed, which could explain the variations we observed in the active layer thickness and permafrost temperatures. Therefore, in late 2015 our research group started the PERMASNOW project (2015-2019) to pay attention to the effect of snow cover on ground thermal This project had two different ways to study the snow cover. On the first hand, in early 2017 we deployed new instrumentation, including new time lapse cameras, snow poles with high number of sensors and a complete and complex set of instruments and sensors to configure a snow pack analyzer station providing 32 environmental and snow parameters. We used the data acquired along 2017 and 2018 years with the new instruments, together with the available from all our already existing sensors, to study in detail the snow cover. On the other hand, remote sensing data were used to try to map the snow cover, not only at our monitoring stations but the entire islands in order to map and study the snow cover distribution, as well as to start the way for future permafrost mapping in the entire islands. MODIS-derived surface temperatures and albedo products were used to detect the snow cover and to test the surface temperature. Since cloud presence limited the acquisition of valid observations of MODIS sensor, we also analyzed Terrasar X data to overcome this limitation. Remote sensing data validation required the acquirement of in situ ground-true data, consisting on data front our permanent instruments, as well as ad hoc measurements in the field (snow cover mapping, snow pits, albedo characterization, etc.). Although the project is finished, the data analysis is still ongoing. We present here the different research tasks we are developing as well as the most important results we already obtained about the snow cover. These results confirm how the snow cover duration has been changing in the last years, affecting the ground thermal behavior.
Acceso Abierto
In-flight calibration of the MEDA-TIRS instrument onboard NASA's Mars2020 mission
(Elsevier, 2024-11-09) Sebastián, E.; Martínez, Germán M.; Ramos, Miguel; Smith, Michael D.; Peinado, V.; Mora Sotomayor, L.; Lemmon, M. T.; Vicente Retortillo, Álvaro; de Lucas Veguillas, Javier; Ferrándiz, Ricardo; Rodríguez Manfredi, J. A.
This article describes a novel procedure and algorithm used for the in-flight calibration of the Thermal Infrared Sensor (TIRS) onboard the Mars 2020 mission. The purpose is to recalibrate the responsivity of TIRS’ IR detectors as they degrade following surface operations and exposure to harsh environmental conditions. Using data from in-flight calibration campaigns conducted through sol 800 of this mission, we report the time evolution of the responsivity for the different IR detectors, as well as the final performance achieved by the algorithm in the real operating environment. Moreover, we analyzed changes in responsivity as a function of TIRS geometric design and environmental factors, e.g., detector orientation, direct exposure to prevailing winds and solar radiation, electrostatic properties of the detector filter, and atmospheric dust concentration. We concluded that dust deposition on the detectors' filter during landing, and later during operation is the most likely cause of the degradation observed in the various channels, with gravitational sedimentation and the capacity of the filters to accumulate electrostatic charge being key factors. The relative and absolute degradation of the TIRS is similar to those reported by other Martian missions and instruments with similar orientations, and to date, it has shown no signs of cleaning after more than a year on the surface of Mars. Accounting for changes in responsivity during the mission is critical to maintaining the reliability of TIRS measurements, which will later be made available in NASA's Planetary Data System for the benefit of the scientific community.
Restringido
Performance analysis of the MEDA's Thermal InfraRed Sensor (TIRS) on board the Mars 2020
(Institute of Electrical and Electronics Engineers, 2017-06-23) Sebastián, E.; Pérez, Joel; Bravo, Andrés; Ferrándiz, Ricardo; Fernández, Maite; Rodríguez Manfredi, J. A.; Martínez, G.; Peña, A.; González, David; Moreno, José; De Lucas Veguillas, Javier; Hernández, Pedro; Pérez Grande, I.; Chamorro, Adrián; Ramos, Miguel; Instituto Nacional de Técnica Aeroespacial (INTA)
The Thermal InfraRed Sensor (TIRS), an infrared (IR) radiometer developed at Centro de Astrobiología, is one the sensors that compose the Mars Environmental Dynamics Analyzer (MEDA) onboard NASA's Mars 2020 mission. It will measure the net thermal infrared radiation, reflected solar radiation at the surface, atmosphere temperature and surface skin brightness temperature using five different channels. The present paper provides a brief description on TIRS design and channels requirements. Then, a detailed presentation of sensor model equations and a sensitivity analysis to model uncertainties are included. Finally, accuracy and resolution calculus for each channel versus operational temperature is presented. The calculus is performed based on sensitivity equations and the estimated values for different uncertainties sources.
Restringido
Radiometric and angular calibration tests for the MEDA-TIRS radiometer onboard NASA’s Mars 2020 mission
(Elsevier BV, 2020-11-02) Sebastián, E.; Martínez, Germán M.; Ramos, Miguel; Haenschke, F.; Ferrándiz, Ricardo; Fernández Sampedro, M.; Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Fernández Sampedro, M. [0000-0003-1932-7591]; Rodríguez Manfredi, J. A. [0000-0003-0461-9815]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
This article describes a comprehensive testing method for the radiometric and angular calibration of the Thermal InfraRed Sensor (TIRS) onboard NASA’s Mars 2020 mission. First, details of the TIRS opto-mechanical design, construction aspects of the IR detectors, and an update of the mathematical model used for the calculation of sensor internal IR fluxes are provided. Then, a set of sequential calibration tests to identify the radiometer model parameters are defined. The test setups are described, highlighting their limitations and restrictions based on differences between simulated and actual Martian environmental conditions. Finally, the uncertainty sources and potential systematic errors associated with the calibration tests are quantified and compared with the radiometer scientific requirements established by the Mars 2020 science team.
Acceso Abierto
Surface Energy Budget, Albedo, and Thermal Inertia at Jezero Crater, Mars, as Observed From the Mars 2020 MEDA Instrument
(AGU Advancing Earth and Space Science, 2023-02) Martínez, Germán M.; Sebastián, E.; Vicente Retortillo, Álvaro; Smith, Michael D.; Johnson, J. R.; Fischer, E.; Savijärvi, H.; Toledo, D.; Hueso, R.; Mora Sotomayor, L.; Gillespie, H.; Munguira, A.; Sánchez Lavega, Agustín; Lemmon, M. T.; Gómez, Felipe; Polkko, J.; Mandon, Lucía; Apéstigue, Víctor; Arruego, Ignacio; Ramos, Miguel; Conrad, Pamela G.; Newman, C. E.; De la Torre Juárez, M.; Jordan, Francisco; Tamppari, L. K.; McConnochie, Tim H.; Harri, Ari-Matti; Genzer, María; Hieta, M.; Zorzano, María-Paz; Siegler, M.; Prieto-Ballesteros, Olga; Molina, A.; Rodríguez Manfredi, J. A.; Comunidad de Madrid; Universities Space Research Association (USRA); Agencia Estatal de Investigación (AEI); Gobierno Vasco; Instituto Nacional de Técnica Aeroespacial (INTA); Centre National D'Etudes Spatiales (CNES); National Aeronautics and Space Administration (NASA); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The Mars Environmental Dynamics Analyzer (MEDA) on board Perseverance includes first-of-its-kind sensors measuring the incident and reflected solar flux, the downwelling atmospheric IR flux, and the upwelling IR flux emitted by the surface. We use these measurements for the first 350 sols of the Mars 2020 mission (Ls ∼ 6°–174° in Martian Year 36) to determine the surface radiative budget on Mars and to calculate the broadband albedo (0.3–3 μm) as a function of the illumination and viewing geometry. Together with MEDA measurements of ground temperature, we calculate the thermal inertia for homogeneous terrains without the need for numerical thermal models. We found that (a) the observed downwelling atmospheric IR flux is significantly lower than the model predictions. This is likely caused by the strong diurnal variation in aerosol opacity measured by MEDA, which is not accounted for by numerical models. (b) The albedo presents a marked non-Lambertian behavior, with lowest values near noon and highest values corresponding to low phase angles (i.e., Sun behind the observer). (c) Thermal inertia values ranged between 180 (sand dune) and 605 (bedrock-dominated material) SI units. (d) Averages of albedo and thermal inertia (spatial resolution of ∼3–4 m2) along Perseverance's traverse are in very good agreement with collocated retrievals of thermal inertia from Thermal Emission Imaging System (spatial resolution of 100 m per pixel) and of bolometric albedo in the 0.25–2.9 μm range from (spatial resolution of ∼300 km2). The results presented here are important to validate model predictions and provide ground-truth to orbital measurements.
Acceso Abierto
The diverse meteorology of Jezero crater over the first 250 sols of Perseverance on Mars
(Nature Publishing Group, 2023-01-09) Rodríguez Manfredi, J. A.; De la Torre Juárez, M.; Sánchez Lavega, Agustín; Hueso, R.; Martínez, Germán M.; Lemmon, M. T.; Newman, C. E.; Munguira, A.; Hieta, M.; Tamppari, L. K.; Polkko, J.; Toledo, D.; Sebastian, D.; Smith, Michael D.; Jaakonaho, I.; Genzer, María; Vicente Retortillo, Álvaro; Viúdez Moreiras, Daniel; Ramos, Miguel; Saiz López, A.; Lepinette Malvitte, A.; Wolff, Michael; Sullivan, R. J.; Gómez Elvira, J.; Apéstigue, Víctor; Conrad, P.; Del Río Gaztelurrutia, T.; Murdoch, N.; Arruego, Ignacio; Banfield, D.; Boland, J.; Brown, Adrian Jon; Ceballos Cáceres, J.; Domínguez Pumar, M.; Espejo, S.; Fairén, A.; Ferrándiz Guibelalde, Ricardo; Fischer, E.; García Villadangos, M.; Giménez Torregrosa, S.; Gómez Gómez, F.; Guzewich, Scott; Harri, Ari-Matti; Jiménez Martín, Juan José; Jiménez, V.; Makinen, Terhi; Marín Jiménez, M.; Martín Rubio, C.; Martín Soler, J.; Molina, A.; Mora Sotomayor, L.; Navarro López, Sara; Peinado, V.; Pérez Grande, I.; Pla García, J.; Postigo, M.; Prieto-Ballesteros, Olga; Rafkin, Scot C. R.; Richardson, M. I.; Romeral, J.; Romero Guzmán, Catalina; Savijärvi, H.; Schofield, J. T.; Torres, J.; Urquí, R.; Zurita, S.; NASA Jet Propulsion Laboratory (JPL); National Aeronautics and Space Administration (NASA); Instituto Nacional de Técnica Aeroespacial (INTA); European Commission (EC); Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); California Institute of Technology (CIT); Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
NASA’s Perseverance rover’s Mars Environmental Dynamics Analyzer is collecting data at Jezero crater, characterizing the physical processes in the lowest layer of the Martian atmosphere. Here we present measurements from the instrument’s first 250 sols of operation, revealing a spatially and temporally variable meteorology at Jezero. We find that temperature measurements at four heights capture the response of the atmospheric surface layer to multiple phenomena. We observe the transition from a stable night-time thermal inversion to a daytime, highly turbulent convective regime, with large vertical thermal gradients. Measurement of multiple daily optical depths suggests aerosol concentrations are higher in the morning than in the afternoon. Measured wind patterns are driven mainly by local topography, with a small contribution from regional winds. Daily and seasonal variability of relative humidity shows a complex hydrologic cycle. These observations suggest that changes in some local surface properties, such as surface albedo and thermal inertia, play an influential role. On a larger scale, surface pressure measurements show typical signatures of gravity waves and baroclinic eddies in a part of the seasonal cycle previously characterized as low wave activity. These observations, both com
Acceso Abierto
The Mars Environmental Dynamics Analyzer, MEDA. A Suite of Environmental Sensors for the Mars 2020 Mission
(Springer Link, 2021-04-13) Rodríguez Manfredi, J. A.; De la Torre Juárez, M.; Alonso, A.; Apéstigue, Víctor; Arruego, Ignacio; Atienza, T.; Banfield, D.; Boland, J.; Carrera, M. A.; Castañer, L.; Ceballos Cáceres, J.; Chen Chen, H.; Cobos, A.; Conrad, Pamela G.; Cordoba, E.; Del Río Gaztelurrutia, T.; Vicente Retortillo, Álvaro; Domínguez Pumar, M.; Espejo, S.; Fairén, Alberto G.; Fernández Palma, A.; Ferrándiz, Ricardo; Ferri, F.; Fischer, E.; García Manchado, A.; García Villadangos, M.; Genzer, María; Giménez, Á.; Gómez Elvira, J.; Gómez, Felipe; Guzewich, Scott; Harri, Ari-Matti; Hernández, C. D.; Hieta, M.; Hueso, R.; Jaakonaho, I.; Jiménez Martín, Juan José; Jiménez, V.; Larman, A.; Leiter, R.; Lepinette Malvitte, A.; Lemmon, M. T.; López, G.; Madsen, Soren N.; Mäkinen, T.; Marín Jiménez, M.; Martín Soler, J.; Martínez, Germán M.; Molina, A.; Mora Sotomayor, L.; Moreno Álvarez, J. F.; Navarro López, Sara; Newman, C. E.; Ortega, Cristina; Parrondo, María Concepción; Peinado, V.; Peña, A.; Pérez Grande, I.; Pérez Hoyos, S.; Pla García, J.; Polkko, J.; Postigo, M.; Prieto-Ballesteros, Olga; Rafkin, Scot C. R.; Ramos, Miguel; Richardson, M. I.; Romeral, J.; Romero Guzmán, Catalina; Runyon, Kirby; Saiz López, A.; Sánchez Lavega, Agustín; Sard, I.; Schofield, J. T.; Sebastián, E.; Smith, Michael D.; Sullivan, Robert; Tamppari, L. K.; Thompson, A. D.; Toledo, D.; Torrero, F.; Torres, J.; Urquí, R.; Velasco, T.; Viúdez Moreiras, Daniel; Zurita, S.; Agencia Estatal de Investigación (AEI); European Research Council (ERC); Gobierno Vasco; Rodríguez Manfredi, J. A. [0000-0003-0461-9815]; Saiz López, A. [0000-0002-0060-1581]; Chen, H. [0000-0001-9662-0308]; Pérez Hoyos, S. [0000-0002-2587-4682]
NASA’s Mars 2020 (M2020) rover mission includes a suite of sensors to monitor current environmental conditions near the surface of Mars and to constrain bulk aerosol properties from changes in atmospheric radiation at the surface. The Mars Environmental Dynamics Analyzer (MEDA) consists of a set of meteorological sensors including wind sensor, a barometer, a relative humidity sensor, a set of 5 thermocouples to measure atmospheric temperature at ∼1.5 m and ∼0.5 m above the surface, a set of thermopiles to characterize the thermal IR brightness temperatures of the surface and the lower atmosphere. MEDA adds a radiation and dust sensor to monitor the optical atmospheric properties that can be used to infer bulk aerosol physical properties such as particle size distribution, non-sphericity, and concentration. The MEDA package and its scientific purpose are described in this document as well as how it responded to the calibration tests and how it helps prepare for the human exploration of Mars. A comparison is also presented to previous environmental monitoring payloads landed on Mars on the Viking, Pathfinder, Phoenix, MSL, and InSight spacecraft.
Acceso Abierto
Transition from a Subaerial to a Subnival Permafrost Temperature Regime Following Increased Snow Cover (Livingston Island, Maritime Antarctic)
(Multidisciplinary Digital Publishing Institute (MDPI), 2020-12-08) Ramos, Miguel; Vieira, G.; De Pablo, M. A.; Molina, A.; Jiménez, Juan Javier; Ministerio de Ciencia e Innovación (MICINN); Ministerio de Economía y Competitividad (MINECO); Fundacao para a Ciencia e a Tecnologia (FCT); Ramos, M. [0000-0003-3648-6818]; Vieira, G. [0000-0001-7611-3464]; De Pablo, M. Á. [0000-0002-4496-2741]; Jiménez Cuenca, J. J. [0000-0001-7677-8140]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
The Antarctic Peninsula (AP) region has been one of the regions on Earth with strongest warming since 1950. However, the northwest of the AP showed a cooling from 2000 to 2015, which had local consequences with an increase in snow accumulation and a deceleration in the loss of mass from glaciers. In this paper, we studied the effects of increased snow accumulation in the permafrost thermal regime in two boreholes (PG1 and PG2) in Livingston Island, South Shetlands Archipelago, from 2009 to 2015. The two boreholes located c. 300 m apart but at similar elevation showed different snow accumulation, with PG2 becoming completely covered with snow all year long, while the other remained mostly snow free during the summer. The analysis of the thermal regimes and of the estimated soil surface energy exchange during the study period showed the effects of snow insulation in reducing the active layer thickness. These effects were especially relevant in PG2, which transitioned from a subaerial to a subnival regime. There, permafrost aggraded from below, with the active layer completely disappearing and the efficiency of thermal insulation by the snowpack prevailing in the thermal regime. This situation may be used as an analogue for the transition from a periglacial to a subglacial environment in longer periods of cooling in the paleoenvironmental record. View Full-Text